Because Aimz only changes a client-side texture, it works on essentially any server you join — including large PvP networks — without needing server-side permission. The server never sees your crosshair, so there is nothing to configure on their end.

What to Expect on Servers

1. Join any server as normal. Your crosshair will look the same as it does in single-player.

2. Some servers ship their own resource pack that also edits the crosshair. When the server prompts you to accept its pack, that pack may override Aimz.

3. To keep Aimz visible, open Options > Resource Packs after joining and drag Aimz above the server pack in the *Selected* list.

4. Note that server packs are often re-applied on each join, so you may need to repeat this if the server forces its pack to the top.

If the Crosshair Reverts

Check whether the server pack is set to *Required*. If it is, you cannot reorder it, and the server's crosshair wins.
Otherwise, simply move Aimz up and click Done.

Your hit registration, reach, and combat behavior are completely unaffected — only the visual crosshair changes.